After 2 years of searching I still don't own the double disc Little Mermaid DVD! I tried one R1 and another R2 via amazon marketplace and both were dodgy.
Amazon did refund my money and investigate. The customer is not made aware of the results of internal investigations carried out by amazon.
I still have the earlier single disc DVD for now (UK, Region 2, PAL) and have pre-ordered the DVD/Blu-Ray combo-pack here at amazon.com but I'm not sure if there is a release date yet.
BTW, the commentary track is different on the two DVD versions of Sleeping Beauty.
2008 DVD commentary by Pixar's John Lasseter, Disney animator Andreas Déja and film critic/historian Leonard Maltin.
2003 DVD commentary hosted by Jeff Kurtti (Disney Historian) with contributions by Ollie Johnston (Supervising Animator), Marc Davis (Supervising Animator), Eyvand Earle (Art Director), Frank Armitage (Backgrount Painter), Mary Costa (Voice Actress - "Brier Rose"/Aurora), Michael Giaimo (Modern Disney Artist - i.e. he had nothing to do with making the film) & Mike Gabriel (Modern Disney Artist - i.e. he had nothing to do with making the film).